The use of electrical outlet boxes (also referred to herein as outlet boxes) for housing electrical devices and connecting wires is well known in the prior art. These boxes come in a variety of different shapes (typically, square, round and rectangular) and can house electrical receptacle or switches that are mounted in walls for connecting electrical devices and operating lights and appliances. In new construction, a box is typically attached to a wall stud and the front face of the box extends beyond the stud so that it will be flush with the surface of the wall that is attached to the stud. For example, when the wall is formed from one-half inch thick sheet rock, the face of the box extends approximately one-half inch beyond the stud. When a receptacle or switch is installed in the box and a cover plate attached, the cover plate will lie flat on the surface of the wall.
However, the thickness of the wall can sometimes change when a new wall covering is installed over an existing wall. Renovations frequently include the installation of new sheet rock over existing walls. In these cases, the front face of an existing electrical box will not be flush with the new wall surface and may be recessed from the new wall surface by one-half an inch or more. In order to modify the electrical boxes to fit the new wall thickness, a switch box extender must be attached to the existing box. When properly attached, the front face of the extender is flush with the surface of the new wall.
Switch box extenders or extenders, that are currently in use, typically have walls that correspond to the walls of an outlet box and an opening in the middle for accessing the box. An extender for a round box can have a single curved wall, while an extender for a square or rectangular box would have four walls. The extenders generally correspond in size to the electrical box opening so that they can be inserted into the front of the box with the exterior walls of the extender received by the interior walls of the box. A variety of different means are used to secure the extender to the box, including screws, clips and fasteners. An extender is attached to the front face of the existing box and sized so that the front face of the extender is flush with the surface of the new wall covering. Accordingly, these extenders come in different sizes to accommodate different wall thicknesses and electrical outlet boxes of different sizes. Typically, the extenders provide between ⅛-inch and 1-inch of extension to the existing switch box.
The most commonly used extenders for electrical boxes are manufactured by a process that includes a metal stamping step, a folding (or bending) step and a welding step. Typically, these extenders are made from a flat piece of sheet metal which is stamped into a substantially rectangular shape and folded over to form two pairs of opposing side walls with four comers. The corner that is formed by the two ends of the piece of sheet metal are then welded together to complete the extender. For a round box, the ends of a single curved wall are welded together. The cost to produce these extenders is made up mostly by the manufacturing cost since the cost of the raw materials (the sheet metal) is relatively small. Therefore, in order to reduce the production cost, there is a need for extenders that can be manufactured more efficiently and less expensively.